<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .box {
            width: 200px;
            height: 200px;
            background-color: red;
            transition: all 1s,ease-in-out,1s;
        }
        .box:hover{
            background-color: blue;
        }
    </style>

</head>

<body>



    <div class="box">
        123
    </div>
</body>

</html>